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I bind a custom NSMatrix this way :

[myMatrix bind:@”content” toObject:myArrayController withKeyPath:@”arrangedObjects” options:nil];

[myMatrix bind:@”contentValues” toObject:myArrayController withKeyPath:@”arrangedObjects.title” options:nil];

And that work fine with title, but what can I do if i want to bind pictures of the NSCell ? Can I define a method in my NSMatrix subclass wich the bind “content” will use ?